Directing his first feature in New York last summer on an indie budget, "Our carbon footprint was so light on every level," says Josh Radnor, who also stars in the charming "Happythankyoumoreplease," opening March 4. "I'm personally trying to do what I can, and I will probably pay more attention to it as I go," he says.

Writing short stories and then scripts on his time off from "How I Met Your Mother," Radnor came up with a story about a young guy who takes in a child separated from his foster parent on the subway, mixing it with threads about relationships — his friends' and his own. "So much of the movie is me. I think I'm in every character," says Radnor who cast Kate Mara, Malin Akerman and newcomer Michael Algieri, now 10, in key roles.

He sees the film as a needed antidote to bleak movies that dwell on the negative, fear-based, cynical, pessimistic and joyless aspects of life. "I think we just live in a society that's always telling us what's wrong with ourselves. The morning paper is so alarmist: 'Here's everything that's going wrong.' It requires more vigilance and work to go to that other place, but it's so much more worth it," believes Radnor, for whom hopelessness "is not my reality. I surround myself with positive, interesting people and go towards the thing that's kinder, more compassionate, more forgiving, all those things we would most want to encourage in the world. I'm a mess, like everyone else," he qualifies, "but I'm doing my best."

The challenges of writing, directing, acting and supervising every other aspect of the movie were considerable, Radnor acknowledges, imagining it to be like childbirth: "I forget the pain of it. But it was really joyful because I surrounded myself with such good people and I believed in the story I was telling. I felt just happy to be there. I'm going to do it again so it couldn't have been all that bad," he says, mum on the details. "I've got something in the works, but I'm not talking about it."

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Josh Radnor keeps it green on directorial debut, 'Happythankyoumoreplease'
'How I Met Your Mother' star tries his hand at directing — and green.